Consolidated Statements of Comprehensive Income (USD $) In Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Consolidated Statements of Comprehensive Income
Net (loss) income	$ (31.8)	$ 2.3	$ (2.5)	$ 44.1
Available-for-sale securities:
Net appreciation during the period	37.3	66.3	37.5	121.4
Portion of other-than-temporary impairment losses transferred from other comprehensive income	2.1	1.7	5.4	4.3
(Provision) benefit for deferred federal income taxes	(2.3)	(11.2)	0.8	(31.5)
Total available-for-sale securities	37.1	56.8	43.7	94.2
Derivative instruments:
Net depreciation during the period	(1.9)		(1.9)
Benefit for deferred federal income taxes	0.7		0.7
Total derivative instruments	(1.2)		(1.2)
Amortization recognized as net periodic benefit costs:
Net actuarial loss	3.8	4.3	7.7	8.6
Prior service cost	(1.3)	(1.5)	(2.6)	(2.9)
Transition asset		(0.4)		(0.8)
Total amortization recognized as net periodic benefit costs	2.5	2.4	5.1	4.9
Provision for deferred federal income taxes	(0.9)	(0.8)	(1.8)	(1.7)
Total pension and postretirement benefits	1.6	1.6	3.3	3.2
Other comprehensive income	37.5	58.4	45.8	97.4
Comprehensive income	$ 5.7	$ 60.7	$ 43.3	$ 141.5